American potato salad is served chilled, cold. German potato salad is a different recipe and is served warm or hot.
Combine all ingredients. Chill and Serve.
Note: If you like a little zing, try more mustard, or try chow-chow (mild or hot) rather than relish.
Note: For a German-style potato salad, add a small amount of vinegar and/or Sauerkraut, a bit of parsley, and serve warmed. — That may not be the traditional German-style potato salad. The editor/cook is looking for that.